In order to get the (military pay) subtraction option to appear in the TurboTax state of Oregon program module, you first have to "set" or "establish" the conditions for it on the federal side of TurboTax.
Specifically, you first need to tell the program in the Personal information section, at the very beginning, that you have military pay. Second, in the Federal income section, after you enter your relevant W-2 wages, you will want to check the box under "Uncommon Situations" specifying military. Third, after you then complete the rest of your federal tax return, and begin your Oregon state return, the military pay subtraction will "automatically" appear as part of the state interview.
But, if the preconditions have not been correctly set up on the federal side of TurboTax, the Oregon military pop-up will not appear automatically in the state module.
For a visual guide to what we're referring to, please see the screen-capture images attached to this answer, directly beneath this text. You can simply click the images to open.
When carefully followed these steps should lead you to the desired resolution of this issue.
However, if you have further questions, encounter any difficulties with this process, or just want to speak with a live tax expert who can walk you through your TurboTax entries (including the ability to screen-share with your computer), please feel free to contact us. We would be happy to help you (and as a paying customer, the call is free to you). Here is a link where you can create a support ticket and reach us:
Additionally, if you do decide to call us for help on this matter, please be sure to refer the live agent who responds to this exact post on the AnswerXchange. The written explanation here of what must be done (especially on the federal side of the program), as well as the screen-capture images, will not only aid them tremendously in assisting you, but will save you a lot of time on the phone as well.
Thank you for asking this important question.